Eye testing perimeters



Jan. 1, 1963 G. J. E. JAYLE EYE TESTING PERIMETER Filed Aug. 22, .1957

INVEN TOR ATmR/v Y United States Patent 3,071,040 EYE TESTING PERIMETERSGaetan Jean Edouard Jayle, 79 Rue du Docteur-Escat, Marseille 6, FranceFiled Aug. 22, 1957, Ser. No. 679,611 Claims priority, applicationFrance Aug. 29, 1956 3 Claims. (Cl. 88-20) The present invention relatesto ophthalmological apparatus for checking up the vision of a patientand in particular to perimeters, such apparatus comprising a bowl havingan at least approximately part-spherical inner surface, the p-atientseye being located at the center of said surface and light projectingmeans capable of forming a luminous spot at any desired point on saidsurface.

The object of my invention is to provide an apparatus of this kind whichis better adapted to meet the requirements of practice than those usedup to this time.

For this purpose, according to my invention, said bowl is journalledabout the central axis of said surface and may be rotated throughsuitable means about said axis, and the light projecting means aremovably carried by said bowl and actuated through suitable means todisplace said luminous spot on a given great circle of said sphericalsurface located in a plane passing through said central axis.

Other features of my invention will become apparent in the course of thefollowing detailed description of an embodiment thereof, with referenceto the appended drawing, given merely by way of example and in which:

FIG. 1 is an elevational view partly in vertical section of a perimetermade according to my invention.

FIG. 2 is the corresponding perspective view.

The apparatus illustrated by the drawing comprises the followingelements:

On the one hand, a bowl 1, for instance having a hemispherical innersurface, at the center of which is placed the patients eye, said bowlbeing journalled in the apparatus frame F about an axis 2 passingthrough the central point 0 of said surface;

And on the other hand, a light projecting device carried by bowl 1 andcapable of forming on the inner surface thereof a luminous spot, saidlight projecting device including movable elements arranged in suchmanner that the luminous spot can be displaced on a given great circleof the spherical surface thereof located in a plane passing through saidcentral point 0.

For instance, as shown, thisv light projecting means comprises a tube 33having a light source therein, the tube having an end face 3 mounted at45 from the vertical on the lower end of the tube. The axis of the tube33 passes through the center of spherical bowl 1 and the tube is mountedso as to be pivotable in casing 12 about said axis. The tube 33 is rigidwith a worm wheel 11 surrounding it and the worm wheel meshes with aworm 41 fixed on the shaft of motor 10. A light source within tube 33sends a light beam to form the luminous spot on the inner surface ofbowl 1. The source is mounted in a fixed position with respect to bowl 1so that, when motor 10 rotates tube 33, the luminous spot formed by thebeam from the tube 33 travels along the horizontal meridian circle shownin dotted lines in FIG. 1.

It will thus be possible, by combining the movements of bowl 1 about itsaxis 2 and those of tube 33-, to produce a luminous spot at any desiredpoint with respect to the patients eye.

The movement of rotation of bowl 1 about axis 2 may be obtained throughmanually controlled means including for instance, as visible on FIG. 2,a cable 4 forming a loop wound on a grooved pulley 5 fixed with respectto bowl 1 and rotating about axis 2, said cable being mounted so that itcannot slip with respect to said pulley. Both of the ends of this cableare fixed to a nut 6 movable axially along a screw 7 on which it isscrewed, said screw carrying an operating wheel 8 so as to be movablebetween two end positions limited by abutments 9 and corresponding tothe maximum angular displacements of bowl 1 (for instance 180).

This system is combined with an observation device enabling the operatorto follow on a frosted glass table 13 the displacements of another lightspot emitted from a light projector 14 adapted to be moved with respectto said table with two elementary motions, that is to say a radialmotion and an angular motion.

The displacements of this second mentioned luminous spot are controlledin such manner as to correspond to those of the luminous spot formed onbowl 1.

For this purpose, for every position of the great circle described bythe first luminous spot on bowl 1, there corresponds a straight linedescribed by the second spot on table 13, the different straight linessuch as d which can thus be traced on said table 13 corresponding to thedifferent positions of said great circle of the spherical inner surfaceof bowl 1, when said bowl is rotated about its axis 2.

The circles described by the first luminous spot when the lightprojecting device 3 remains fixed with respect to the bowl and said bowlis rotated about its axis 2 are represented on table 13 by concentriccircles c.

Thus, the indications given by the second spot on table 13 give exactlythe position of the first light spot formed on bowl 1 with respect tothe patients eye.

In order to control the displacements of the second light spot, formedon table 13, in accordance with the displacements of the first spot,formed on bowl 1, I may for instance use the arrangement shown by thedrawing:

The light projector 14 is carried by an annular member 15 capable ofrotating about an axis at right angles to table 13 and passing throughthe central point thereof. For this purpose, this annular member 15 ismounted on a pulley 16.

The axis 2 of bowl 1 carries a pulley of the same diameter as pulley 16(and which may be constituted by the above mentioned pulley 5) andpulleys 16 and 5 are coupled together by means of a semi-rigid cable 17passing around said pulleys in such manner as to be unable to slip withrespect thereto. Cable 17 passes on rollers 18, which permits itstension to be adjusted and to give table 13 the desired inclination.

Thus, when the operator rotates wheel 8 in one direction, he produces arotation in a given direction of :bowl 1 about its axis, which in turnproduces, owing to the transmission constituted by pulleys 5 and 16coupled together by cable 17, a rotation in a given direction of annularmember 15. When the operator turns wheel 8 in the opposed'direction, heproduces a rotation in the opposed direction of member 15.

Furthermore, projector 14 is mounted on a rod 19 extending along adiameter of annular member 15, said projector being always maintained insuch position with respect to said rod that the beam it supplies is atright angles to table 13. Projector 14 is fixed to the central portionof rod 19 and the ends of said rod are provided with two pistons (notvisible on the drawing) slidable in receiver cylinders 20 and 21 carriedby annular member 15 at the ends of a diameter thereof. Said cylinders20 and 21 are connected through conduit 24 with two power cylinders 22and 23, the whole of said cylinders and said conduit being filled with aliquid so that the displacements of pistons slidable in power cylinders22 and 23 are transmitted to the pistons slidable in cylinders 20 .notvisible on'the drawing) are mounted at the ends of a controlling,through an electrical conductor 39, the motor 10 which controls thedisplacements of the light projecting device 3.

Thus, when the operator turns control wheel 28 in one direction, heproduces a displacement in a given direction of rod 25 and therefore acorresponding displacement of rod 19, 50 that the spot formed on table13 is moved along a straight line passing through the center of saidtable 13. Simultaneously, this rotation of wheel 28 produces, throughtransmitter 29 and motor 10, a corresponding displacement of the lightprojecting device 3.

In a general manner, while I have, in the above description, disclosedwhat I deem to be a practical and efficient embodiment of my invention,it should be well understood that I do not wish to be limited thereto asthere might be changes made in the arrangement, disposition and form ofthe parts without departing from the principle of the present inventionas comprehended within the scope of the accompanying claims.

What I claim is:

1. An ophthalmological apparatus which comprises, in combination, aframe, a bowl having an at least approximately hemi-spherical innersurface, said bowl being journalled in said frame about the central axisof said surface, the patients eye being located at the center ofcurvature of the hemi-spherical surface, means for rotating said bowlwith respect to said frame about said central axis, first optical meansincluding a light source movably carried by the edge of said bowl forprojecting a luminous spot directly on the inner surface of said bowl ata point of a given great circle of said spherical surface located in aplane passing through said central axis, means carried by said bowl foractuating said first optical means to cause said luminous spot to bedisplaced on said circle, an observation table carried by said frame ata distance from said bowl, said table having a central point, secondoptical means movable with respect to said table for projecting a lightspot on said table, first control means for moving said second opticalmeans to displace said light spot on straight lines passing through saidcentral point of said table, means for operatively connecting saidcontrol means with said means for actuating said first optical means,second control means for moving said second optical means to displacesaid light spot on circles having their common center at said centralpoint of said table, and means for operatively connecting said secondcontrol means with said means for rotating said bowl about the centralaxis of its surface.

2. An ophthalmological apparatus which comprises, in combination, aframe, a bowl having an at least approximately hemi-spherical innersurface, said bowl being journalled in said frame about the central axisof said surface, the patients eye being located at the center ofcurvature of the hemi-sp'nerical surface, means for rotating said bowlwith respect to said frame about said central axis, first optical meansincluding a light source movably carried by the edge of said bowl forprojecting a luminous spot directly on the inner surface of said bowl ata point of a given great circle of said spherical surface located in aplane passing through said central axis, means carried by said bowl foractuating said first optical means to cause said luminous spot to bedisplaced on said circle, an observation table carried by said frame ata distance from said bowl, said table having a central point, an annularmember pivoted in said frame about an axis perpendicular to said tableand passing through the central point thereof, a light projector forforming a light spot on said table, means carried by said annular memberfor .supporting said light projector therein slidably along a diameterof said annular member, said means being capable of keeping said lightprojector constantly directed at right angles to said table, firstcontrol means for moving said projector along said diameter, first meansfor operatively connecting said control means with said means foractuating said optical means, second control means for rotating saidannular member about its axis, and second means for operativelyconnecting said second control means with said means for rotating saidbowl about the central axis of its surface.

3. An apparatus according to claim 1, in which said second operativelyconnecting means are cable and pulley means.

References Cited in the file of this patent UNITED STATES PATENTS596,044 Meyrowitz et a1 Dec. 21, 1897 926,035 Tomlinson June 22, 19091,618,291 Maggiore Feb. 22, 1927 2,374,854 Feinbloom May 1, 1945 FOREIGNPATENTS 264,664 Switzerland Feb. 1, 1950 991,307 France June 20, 19511,057,488 France Oct. 28, 1953 OTHER REFERENCES Projection Perimetry,Fincham, article in The Optician (British), vol. 122, Issue No. 3147(July 27, 1951), pages 15, 16, and 22.

1. AN OPHTHALMOLOGICAL APPARATUS WHICH COMPRISES, IN COMBINATION, AFRAME, A BOWL HAVING AN AT LEAST APPROXIMATELY HEMI-SPHERICAL INNERSURFACE, SAID BOWL BEING JOURNALLED IN SAID FRAME ABOUT THE CENTRAL AXISOF SAID SURFACE, THE PATIENT''S EYE BEING LOCATED AT THE CENTER OFCURVATURE OF THE HEMI-SPHERICAL SURFACE, MEANS FOR ROTATING SAID BOWLWITH RESPECT TO SAID FRAME ABOUT SAID CENTRAL AXIS, FIRST OPTICAL MEANSINCLUDING A LIGHT SOURCE MOVABLY CARRIED BY THE EDGE OF SAID BOWL FORPROJECTING A LUMINOUS SPOT DIRECTLY ON THE INNER SURFACE OF SAID BOWL ATA POINT OF A GIVEN GREAT CIRCLE OF SAID SPHERICAL SURFACE LOCATED IN APLANE PASSING THROUGH SAID CENTRAL AXIS, MEANS CARRIED BY SAID BOWL FORACTUATING SAID FIRST OPTICAL MEANS TO CAUSE SAID LUMINOUS SPOT TO BEDISPLACED ON SAID CIRCLE, AN OBSERVATION TABLE CARRIED BY SAID FRAME ATA DISTANCE FROM SAID BOWL, SAID TABLE HAVING A CENTRAL POINT, SECONDOPTICAL MEANS MOVABLE WITH RESPECT TO SAID TABLE FOR PROJECTING A LIGHTSPOT ON SAID TABLE, FIRST CONTROL MEANS FOR MOVING SAID SECOND OPTICALMEANS TO DISPLACE SAID LIGHT SPOT ON STRAIGHT LINES PASSING THROUGH SAIDCENTRAL POINT OF SAID TABLE, MEANS FOR OPERATIVELY CONNECTING SAIDCONTROL MEANS WITH SAID MEANS FOR ACTUATING SAID FIRST OPTICAL MEANS,SECOND CONTROL MEANS FOR MOVING SAID SECOND OPTICAL MEANS TO DISPLACESAID LIGHT SPOT ON CIRCLES HAVING THEIR COMMON CENTER AT SAID CENTRALPOINT OF SAID TABLE, AND MEANS FOR OPERATIVELY CONNECTING SAID SECONDCONTROL MEANS WITH SAID MEANS FOR ROTATING SAID BOWL ABOUT THE CENTRALAXIS OF ITS SURFACE.